1. Field of the Invention
The present invention relates to a saddle-ride type vehicle having an engine body mounted between a front wheel and a rear wheel on a body frame. A rear shock absorber is installed between a swing arm and the body frame so as to extend vertically and between a pair of left and right frame members constituting part of the body frame and disposed behind the engine body with the swing arm pivotally supporting the rear wheel and being swingably supported by the body frame. A cleaner case for an air cleaner and intake air control means are connected via a connecting tube disposed to bypass the side of the rear shock absorber, the air cleaner being disposed behind the rear shock absorber with the intake air control means being adapted to control an amount of air supplied from the air cleaner to the engine body. In particular, the invention relates to an improvement in an intake system.
2. Description of Background Art
An intake system for a motorcycle is known as disclosed in Japanese Patent Laid-Open No. Hei 5-172013, wherein a carburetor and a cleaner case for an air cleaner case disposed behind a rear shock absorber are connected by a connecting tube bypassing the rear shock absorber.
In the intake system disclosed in Japanese Patent Laid-Open No. Hei 5-172013, the connecting tube is composed of a tubular connecting tube main body and a sub-chamber. The connecting tube main body bends so as to bypass the rear shock absorber. The sub-chamber is integrally formed with a cleaner case side end portion of the connecting tube main body so as to form an intake chamber together with the cleaner case. The intake chamber constitutes part of a purified-air chamber on the downstream side of a cleaner element of the air cleaner. The connecting tube is formed to have a transverse-sectional shape largely changed from the middle thereof. It is desired, however, to increase the capacity of the intake chamber in order to improve intake performance of an engine, thereby achieving an improved charging efficiency.